Page 263 - Biomedical Engineering and Design Handbook Volume 2, Applications

IEC 60601-2-33
IEC 60601-2-33
controlled mode
IEC 60601-2-33 second controlled mode (operator takes deliberate (needs IRB approval) action to enter) normal mode 4 T > B 0 4 T B 0 2 T < 4 W/kg Whole-body ave SAR > 4 W/kg Whole-body ave. SAR 2 W/kg with 6 min ave. with 6 min ave. 3.2 W/kg Ave. head SAR > 3.2 W/kg Ave. head SAR 3.2 W/kg with 6 min ave. with 6 min ave. 10 W/kg in head Local SAR > 10 W/kg Local SAR 10 W/kg in head 20 W/kg in extremities or trunk, > 20 W/kg in head or trunk,

2.0 T Whole-body ave. SAR with 6 min ave. Ave. head SAR with 6 min ave. Local SAR or trunk, with 6 min ave. 6 min ave. long-term SAR level nerve mean

SAR
B 0 dB/dt
4 W/kg

FDA significant risk criteria (http://www. fda.gov/cdrh/ode/ magdev.html) Whole-body ave. SAR ≥ 3 W/kg 8 W/kg in any gram (head or torso) Sufficient for severe discomfort

MR Safety Standards 4 T > B 0 with 15 min ave. Ave. head SAR > with 10 min ave. Local SAR > N/A N/A

TABLE 8.1 Safety parameter B 0 WB SAR Head SAR Local SAR Partial body SAR Short-term SAR dB/dt

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